\name{getETRadiation}
\alias{getETRadiation}
\title{calculates extraterrestrial radiation for a given latitude on a given day...}
\usage{getETRadiation(latitude, day)}
\description{calculates extraterrestrial radiation for a given latitude on a given day}
\details{calculates extraterrestrial radiation for a given latitude on a given day}
\value{extra terrestrial radiation}
\author{James Long}
\arguments{\item{latitude}{latitude on the earth in decimal degrees}
\item{day}{day of the year (1-365)}}
